The present disclosure relates to a power-supply apparatus.
In the related art, a power-supply apparatus provided with a plurality of energy storage modules is known. For example, Japanese Laid-open Patent Publication No. 2010-239709 A discloses a power-supply apparatus that switches, by a plurality of switches, connection states of a plurality of batteries between a serial connection state and a parallel connection state. By switching the connection states of the plurality of batteries in this manner, it becomes possible to change a voltage of the power-supply apparatus to a desired voltage.
The power-supply apparatus disclosed in Japanese Laid-open Patent Publication No. 2010-239709 A can be used, for example, in an electronic circuit that supplies electric power to a rotating electrical machine (motor generator) of a vehicle through an inverter. In the electronic circuit that supplies electric power to the rotating electrical machine, a capacitor is connected in parallel to the power-supply apparatus in order to smooth an electric power transmitted between energy storage modules and the inverter. In the power-supply apparatus, the switches change the connection states of the energy storage modules and change a voltage in a staircase pattern. However, when the connection states of the plurality of energy storage modules in the power-supply apparatus are switched, due to a rapid change of an output voltage from the power-supply apparatus at the time of switching, a voltage difference with the capacitor and cause a flow may be generated and thus an inrush current flows. Therefore, a trouble may occur in the elements or the switches in the power-supply apparatus or the inverter.
The present disclosure has been made in view of the problems. There is a need for a power-supply apparatus which includes a plurality of energy storage modules and can switch an output voltage in a staircase pattern and supply an electric power to a rotating electrical machine of a vehicle, and suppress troubles in elements or switches of a power-supply apparatus where capacitors are connected in parallel.